Study to measure radioactive levels in California kelp

Cal State Long Beach biology professor Steven Manley is shown holding a small sample of local macrocystis pyrifera kelp. He is working with a group of marine scientists called Kelp Watch 2014.JEBB HARRIS, STAFF PHOTOGRAPHER

Steven Manley

Mentor: Wheeler J. North is known as the father of kelp. Manley worked with him in the 1980's at the Caltech Kerckhoff Marine Lab in Corona Del Mar.

Previous studies on kelp: 2011 Kelp off Southern California was contaminated with short-lived radioisotopes a month after Japan's Fukushima accident.

Kelp Watch 2014: Scientists will take kelp samplings from Baja to North California to study them for radiation levels. The sea water containing radiation is expected to hit California this summer.

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CORONA DEL MAR – Radioactive seawater, contaminated when a tsunami and earthquake damaged the Fukushima nuclear power plant in Japan, is expected to hit Southern California beaches this summer.

To prepare for this, Steven Manley, a Cal State Long Beach biology professor, will launch a scientific study including more than 20 universities and labs. Participants in Kelp Watch 2014 will harvest 15 pounds of giant and bull kelp from 35 sites along the West Coast, from Baja to Sitka Alaska.

Scientists will study the extent of contamination in the ocean’s kelp forests three times this year. The kelp will be dried and ground. Scientists from Lawrence Berkeley National Laboratory at California Berkeley will then test it for radiation levels. Data from the research will be posted on a website expected to be active by March.

Manley, of Laguna Niguel, launched the project to keep the public informed on radiation in kelp along California beaches. In Orange County kelp is found along beaches with rock outcroppings such as Corona Del Mar, Crystal Cove State Beach, Laguna Beach and Dana Point.

There is a large bed of kelp that blankets ocean water from the San Clemente Pier to beaches at Camp Pendleton, including near the now decommissioned San Onofre Nuclear Generating Station.

The project follows an earlier study Manley did on kelp shortly after the Fukushima reactor accident in March 2011. In that study he discovered short-lived radioactive iodine in kelp just a month after the reactor accident.

That radioactivity came over from Japan by steam released into the atmosphere by the crippled reactor. While the radioactivity from rain was low, there were measured amounts inthe ocean plant. Manley said while radioactive iodine has a short life, he detected levels of it in the kelp for at least a month after the reactor accident.

Manley found the largest concentration 250-fold higher than before the accident. Samples taken a month later showed no detectable radiation. Manley said the radiation had no known effect on kelp, fish or marine life.

Still after his study published, emails flooded his inbox and calls rang from surfers and beachgoers from Japan and Australia, asking if being in the ocean or eating seafood posed risks. Public concern prompted him to undertake the new study.

“As every year passes it becomes more diluted but it also becomes more widespread,” he said. “People should know the amount of radioactive material in the kelp.

The seawater expected to strike California shores this summer has been traveling about 1-3 mph. It’s expected to continue flowing until 2016.

“I think the amount will be small, but small doesn’t mean insignificant,” Manley said. “It is imperative that we monitor this coastal forest for any radioactive contaminants that will be arriving this year in the ocean currents from Fukushima disaster.”

Kelp, a complex ecosystem, has long been viewed as a barometer of ocean health. The kelp’s large surface canopy and long, fast-growing stalks act as sponges, as they’re bathed in seawater. Monitoring what the kelp is sucking up will give scientists an idea of the health of the marine eco systems.

Manley said he expects to find concentration of cesium isotopes − a man-made substance in nuclear reactors. He sees kelp as a wall of defense for the shoreline.

In recent years, especially in Laguna Beach, swimmers, surfers, stand-up paddleboarders and marine watchers have seen kelp forests rebound. They report seeing more abalone, sheephead, lobster, tide pool life and shorebirds.

Laguna’s 7.2 miles of beaches last year was among a handful in the state that are part of the nation's most expansive marine reserves. Laguna is the only citywide marine protected area in the U.S.

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Cal State Long Beach biology professor Steven Manley is shown holding a small sample of local macrocystis pyrifera kelp. He is working with a group of marine scientists called Kelp Watch 2014. JEBB HARRIS, STAFF PHOTOGRAPHER
Cal State Long Beach biology professor Steven Manley holds a small sample of local macrocystis pyrifera kelp. Kelp Watch 2014 will take samples of kelp from along the coast to determine any increase in radio activity in kelp caused by contaminated waters arriving from the Fukushima incident. JEBB HARRIS, STAFF PHOTOGRAPHER
A 2010 file photo shows a fishing boat works the edge of the thriving Wheeler North Kelp Reef off shore between San Clemente and San Onofre. THe kelp beds are named for famed kelp researcher California Institute of Technology Professor Wheeler North. FILE PHOTO: JEBB HARRIS, STAFF PHOTOGRAPHER
A 2008 photo from the 22-acre test kelp forest being built by Southern California Edison off the San Clemente coast. That was a success so they are now laying the foundation rocks for a 150-acre kelp forest in the same area., PHOTO COURTESY SOUTHERN CALIFORNIA EDISON

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